Heats of vaporization and gaseous molar heat capacities of ethanol and the binary mixture of ethanol and benzene

A combined system of the Newsham vaporization calorimeter and the Pitzer gaseous heat capacity flow calorimeter were reconstructed with modifications. Both calorimeters were calibrated with benzene, the liquid standard, and were found to be acceptable for measurements, with deviations of 0.4% and 0.9%, respectively. Heats of vaporization of pure ethanol under five pressures and binary mixtures of ethanol and benzene under normal pressure were determined. Gaseous molar heat capacities of pure ethanol under three pressures and of binary mixture of ethanol and benzene at two temperatures were also determined, with anomalies due to association noted. Association of ethanol molecules in the vapor phase was discussed and analyzed, with heats of association and entropy change of association calculated.